LED (Light Emitting Diode) is a sort of semiconductor device that converts an electric current into a light, and is used as a light source for illumination or display devices. In comparison with a conventional light source, LED has relatively excellent characteristics such as an ultra-small size, low power consumption, a long life, a fast reaction time, and the like. Additionally, no use of mercury or any other discharge gas is environmentally friendly.
Meanwhile, LED is used as a white light source, which is formed of a combination of red, green and blue LEDs, a combination of a blue LED and yellow phospher, or a combination of an UV LED and RGB phospher.
However, use of a conventional LED for a white light source may cause a complex structure, a complicated manufacturing process, a poor luminous efficiency, or the like.